Television set which displays analog data relevant to the operation of the television set on its video display

ABSTRACT

The present invention relates to a television set which includes a picture display device, an alpha numerical character generating circuit connected to said device, a control device, means for determining analogue data relating to the operation of the set, such as volume, brightness and color, and means for displaying on said display device a combination of alpha numerical characters, supplied by said character generating device, indicating the values of said analogue data. 
     A control keyboard has six keys &#34;V+&#34;, &#34;V-&#34;, &#34;L+&#34;, &#34;L-&#34;, &#34;C+&#34; and &#34;C-&#34;. The output of the keyboard is connected to a processing unit which is connected via a digital to analogue converter and switch to an alpha numerical character generator which is connected to a picture display device. When one of the six keys is pressed a combination of signals proportional to the analogue signal level of volume, brightness and color (V, L, C) is displayed on the picture display device. If one of the + keys is pressed, the corresponding analogue level is increased by 1/64 of maximum value, while a similar decrease is obtained by pressing one of the - keys.

BACKGROUND OF THE INVENTION

The present invention relates to a television set which includes apicture display device, an alpha numerical character generating circuitconnected to the said device, a control device and means for checkinganalogue data relating to the operation of the set, such as volume,brightness and color. The system commonly used on television receiversfor tuning into the required channels is the so-called FREQUENCYSYNTHESIZER system. This system, made possible by the advent ofintegrated circuits, offers a number of advantages over other knownsystems, such as the conventional potentiometer type MECHANICAL MEMORYsystems and the more recent so-called VOLTAGE SYNTHESIZER systems. Thefrequency synthesizer system is fully electronic enabling any channel tobe called up directly by the user who formulates the channel number on akeyboard or other control device. The system usually consists of aquartz-controlled reference oscillator, a phase lock loop, aprogrammable divider and a computer which supplies the number to be sentto the programmable divider in response to the number of the channel setby the user. Thanks to the phase lock loop, for each channel number setby the user, the frequency of the local oscillator on the set is kept sostable and accurate that the set is tuned with great precision to thecorresponding channel signal. For further details concerning frequencysynthesizer tuning systems, refer to the article entitled "A FrequencySynthesizer for Television Receivers" by E. G. Breeze, published in theNovember, 1974 issue of the "Transactions BTR" Magazine, or "DigitalTelevision Tuner Uses MOS LSI and Non Volatile Memory" by L. Penner,published in the April 1, 1976 issue of "Electronics".

The frequency synthesizer system lends itself well to a number ofdifferent modes of television chanel tuning;

direct selection by formulating the required channel number as describedabove television channels are numbered: for example, in the EuropeanC.C.I.R. standard, V.H.F. band channels are numbered from 2 to 12 andU.H.F. band channels from 21 to 69; in the American Standard, VHFchannels are numbered from 2 to 13 and UHF from 14 to 83).

memory selection: each of a certain set of keys corresponds to apreselected and memorised channel;

automatic scanning of all the channels of a given standard, or of allthe channels contained in the memory or continuous scanning of all thefrequency bands involved.

The first application enables immediate, direct selection of any one ofthe channels in the relative standard (60 in Europe, 82 in America).

the second enables faster detection of one of a limited number ofpreferred channels.

The third is a fast, simple way of finding out which standard channelscan be received, which channels have been memorised and whether otherbroadcasting stations exist on non-standard frequencies such as theprivate broadcasting stations in Italy (there are currently over ahundred operating).

Examples of frequency synthesizer systems with this wide range ofselection modes are described in West German Patent Applications No. 2645 833 and 26 52 185 and, in particular, Italian Patent Application No.69.950-A/77 filed on Dec. 30, 1977 by the present applicant. All thesemodes, which are particularly useful in areas where a number ofbroadcasting stations can be received, require highly complex controlequipment which many users may find difficulty in operating. This iseven more so if, besides emitter selection and standard receiveradjustment controls (volume, brightness, colour, etc.), provision isalso made for additional accessory functions such as a digital clockwhich requires additional setting controls. Provision of a charactergenerator capable of displaying alpha numerical data on the televisionscreen could prove beneficial in connection with this problem. The aimof the present invention is to provide a television receiver enablingthe many functions described above to be effected simple andinexpensively with as little operating difficulty as possible on thepart of the user.

BRIEF SUMMARY OF THE INVENTION

According to the present invention there is provided a television setincluding a picture display device, an alpha numerical charactergenerating circuit connected to said device, a control device and meansfor determing analogue data relating to the operation of the set whereinmeans are provided for displaying on the picture device a combination ofalpha numerical character, supplied by said character generatingcircuit, indicating the values of said analogue data.

BRIEF DESCRIPTION OF THE DRAWING

The invention will now be described by way of example only and withreference to the accompanying drawings, in which:

FIG. 1 shows the block diagram of part of a television receiveraccording to the present invention;

FIGS. 2, 3 and 4 show block diagrams of elementary logic functionsperformed by the circuits on the device according to the presentinvention;

FIGS. 5 and 6 show a number of FIG. 1 circuits in greater detail.

FIG. 7 shows the block diagram of an improved version of the FIG. 1circuit-only the differing features are shown.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIG. 1, indicates a receiving aerial connected tovaricap-diode tuner 2 at the output of which a signal converted tointermediate frequency IF is available. The tuner is the known type andconsists essentially of a selective amplifier stage, a mixer circuit andlocal oscillator circuit.

One output on the local oscillator circuit is connected to a firstfrequency-divider circuit 3 which divides by a fixed number N1 and whoseoutput is connected to the signal input of a second divider 4 whichdivides by a variable number N with 12-bit programming, which means itcan divide by any number from 1 to 2¹².

The output of divider 4 is connected to a first input of phase-frequencycomparator circuit 5 to whose second input a reference signal generatedby quartz generator 6 is sent via a third frequency-divider circuit 7.The output of comparator circuit 5 is connected to the tuner circuitvaricap diode voltage control input via amplifier and filtering circuit8.

Number 10 indicates a control unit consisting of a keyboard which,besides the control keys not shown, such as the on/off switch andvolume, brightness, contrast and color adjustment controls, alsocontains 10 number keys marked 0 to 9 (or letter keys marked A, B, C, D,E, F, G, H, I, L) and 7 auxiliary keys marked +, -, T, C, OR, M, CT (or+, -, R1, R2, R3, R4, CT).

This control unit is connected to a first group of eight input-outputterminals of processing unit 11 and to the address inputs of memorycircuit 12. The processing unit 11 also has a second set of eightinput-output terminals connected to the data input-output terminals ofmemory circuit 12 and the inputs of character generator circuit 16.This, in turn, is connected to display device 9 (including the kinescopeon the set) while a third group of 16 terminals is connected to:

12 programming inputs of 12-bit divider 4;

2 band-switch inputs (U and BIII) of tuner 2;

1 control input of character generator circuit 16;

a first input of combiner circuit 14.

Memory circuit 12 has further control terminals connected to the outputof combiner circuit 14 which receives a signal from circuit 11 at asecond input and a signal from on-detector circuit 15 at a third.Circuit 15 receives a signal from the power mains the television set isconnected to and also has its output connected to a RESET input ofcircuit 11. Memory 12 and the low-current-absorption CMOS combinercircuit 14 are connected to a local battery supply source 13. Thecircuit operates as follows:

Circuits 3, 4, 5 and 8, together with the varicap-diode-controlled localoscillator (VCO) in tuner 2, form a phase lock loop controlled by thereference signal generated by quartz generator 6 and divided by divider7 according to the known technique.

The function of divider circuit 3 is to reduce the frequencies involvedto more easily processable levels while programmable divider 4 enableslocking to be affected for a number of local oscillator frequencies,that is, it acts as a frequency synthesizer circuit.

In fact, after selecting division number N for divider circuit 4,phase-frequency comparator 5 supplies circuit 2, via amplifier 8, withvoltage for obtaining the following condition:

    f6/N.sub.2 =f2/N.sub.1.N                                   (1)

or

    f2=P.N                                                     (2)

in which f2 is the oscillation frequency of the local oscillator circuitin tuner 2, f6 is the oscillation frequency of reference oscillatorcircuit 6, N₂, N₁ and N are the division ratios of dividers 3, 6 and 4respectively, while P=f6 N1/N₂ indicates the system pitch, that is, theamount by which local oscillator frequency varies alongside variationsin number N.

The receiver must be capable of tuning into broadcasting stations of agiven transmission standard, e.g. C.C.I.R./B-G, with channeling asagreed at the 1961 European Radio Broadcasting Conference in Stockholm,that is, broadcasting stations with one-step spacing between adjacent 7MHz channels on the I and III (VHF) bands and 8 MHz channels on the IVand V (UHF) bands with a 5 MHz video signal band width. Thesebroadcasting stations fall within television channels 2 and 69 (videocarrier frequencies 48.25 and 855.25 MHz respectively) with 38.9 MHzintermediate frequency IF. This means the local oscillator on the tunermust be capable of generating frequencies ranging from 87.15 to 894.15MHz. A 0.25 MHz pitch was selected which, according to equation 2 givesthe following values for the two abovementioned channels: ##EQU1## Byvarying number N between this maximum and minimum, any televisionchannel on the VHF and UHF bands can be tuned into with a maximum errorof 125 KHz. Not all of this frequency range can be utilized so the tuneris provided with two band switch inputs U (UHF/VHF) and B (BIII/BI) toensure only effective bands are covered. Divider 3 is a high-speed ECLtype which divides by 64 (SP 8750). Divider 4 is a programmable TTLwhich can operate up to frequencies of about 15 MHz (3×SN74LS191).Circuits 5, 6 and 7 consist of an SP8760 integrated circuit with 250 KHzfrequency quartz and N₂ =64 division ratio so that comparator circuit 5operates at 3906.25 Hz frequency which corresponds to a quarter of linefrequency. The function of amplifier and filter 8 is to adapt the outputlevel of comparator 5 (max. 5 V) to the requirements of tuner 2 (max. 30V) and provide the best possible filtering and lock speed conditions.

Circuit 11, which consists of a microprocessor unit, is designed togenerate, among other things, N numbers and bandswitch signals fortuning into specific television broadcasting stations on the basis ofdata relative to the signals being tuned into supplied by the user fromcontrol keyboard 10. The said circuit 11 is also capable of supplying orreceiving signals from memory 12 and sending signals to charactergenerating circuit 16. Number N is calculated using the followingequation:

    N=(K·F+C)·4+S                            (1)

The operations shown are performed by means of a series of elementaryoperations by an arithmetical-logic unit (ALU) on the basis ofinstructions contained in a (ROM) program memory contained in the saidprocessing circuit 11 and performed, in this case, using an F8microprocessor. Constant correction C and factor F depend on the bandselected; K is the channel number according to the said standard and theS variable can be changed for performing fine tuning corrections.

If channel number K is changed, we only get the frequenciescorresponding to standard channels with a pitch equal to F (8 MHz forUHF and 7 for VHF), whereas one-unit variation of S causes frequencyshifts of 0.25 MHz. With appropriate control from the keyboard, variousmodes are possible for tuning into a given broadcasting station partlyusing known methods.

Whenever any one of the keys is pressed, processing unit 11 sends anISO-coded 48-character sequence to character generator 16 which isdisplayed on the television screen in a three 16-character linearrangement.

This sequence always includes a time indication (hours, minutes,seconds). The remainder consists partly of fixed data from the ROMprogram memory (e.g. "CHANNEL" and "KEY" shown in FIG. 1) and partly ofvariable data depending on the controls activated by the user and thesituation resulting from them which is memorized in a memory bufferinside unit 11 (e.g. the letter T indicating operation mode in the topright-hand corner of FIG. 1; FIGS. 21-01, also in FIG. 1 following the"CHANNEL" indication which show the channel number and tuningcorrection).

The time indication is corrected automatically each second even if nokey is pressed. When one of the "T", "C", "OR" or "M" keys is pressed,the corresponding operation mode is set and memorized in the memorybuffer of processing unit 11. At the same time, one or more questionmarks are entered into the buffer at appropriate points to guide theuser on the next control operation. The content of the buffer is thentransmitted, of course, to the character generator and displayed on thetelevision screen.

A few examples will now be given to give a clearer idea of this point.

When key "T" is pressed, the display shows:

    ______________________________________                                                   OO:MM:SS T                                                                    KEY      ?                                                         ______________________________________                                    

In this way, the user is informed that he has selected mode "T" (memoryselection) and that the device expects a number key to be pressed (thatis, an emitter memory key number). N.B.: OO:MM:SS in the above examplestands for the time indication (hours, minutes, seconds).

When key "C" is pressed, the display shows:

    ______________________________________                                                   OO:MM:SS C                                                                    CHANNEL  ??                                                        ______________________________________                                    

In this way, the user is informed that he has selected mode "C" (directselection) and that the device expects two number keys to be pressed(required channel number).

If the number formulated by these two keys corresponds to a channel inthe standard, the number will be displayed in place of the two questionmarks beside the "CHANNEL" indication. If the channel number does notcorrespond to one in the standard, the display shows:

    ______________________________________                                                 OO:MM:SS       C                                                              CHANNEL  ??                                                                                        88                                              ______________________________________                                    

In this way, the user is informed that the control set (channel 88 notcovered by the C.C.I.R. standard) has not been performed and that thedevice is awaiting further instructions. When key "OR" is pressed, thedisplay shows:

    ______________________________________                                                  ??:??:??   T                                                                  CHANNEL    21+01                                                              KEY        O  OR                                                    ______________________________________                                    

This tells the user that the television set is still set to mode "T",that it is tuned to channel 21 with a tuning correction equivalent toone frequency shift over 250 KHz, memorized on key 0, and that thedevice expects six number keys to be pressed one after the othercorresponding to the hours, minutes and seconds the clock is to be resetto. As the said six keys are pressed, the corresponding number isdisplayed in place of the "OR" indication and pairs of numbers replacethe "??" corresponding to the hours, minutes and seconds, provided thenumbers are acceptable. In fact, the device checks the set numbers and,if the hour number is over 23 or the number corresponding to the tens ofthe minutes or seconds over 5, the two numbers (hours, minutes orseconds) are rejected and the two question marks are left displayed toinform the user that the device is waiting for another pair ofacceptable numbers to be set. After the operation has been performed,the clock starts counting from the time set by the user. The device isso designed that, following a power cut, a series of zeros is displayedfor the hours, minutes and seconds and the clock remains in thiscondition to inform the user that the power supply has temporarily beencut off.

When the "M" key is pressed, the display shows:

    ______________________________________                                                  OO:MM:SS T                                                                    CHANNEL  21+01                                                                KEY  # ? M                                                          ______________________________________                                                   This tells the user that the television is still set to "T"     mode, that it is tuned to channel 21 with +01 tuning and that the set is     waiting for a number key to be pressed to memorise the channel tuned into.     If key "0" is pressed, for example, the display shown in FIG. 1 appears     and the said channel is associated with key "0" for memory selection. If     key "+" is pressed, the display shows:

    ______________________________________                                                  OO:MM:SS T                                                                    CHANNEL  21+02                                                                KEY  O                                                              ______________________________________                                    

This tells the user that the television is still set to "T" mode and theexcess tuning corrections are being made, that is, towards the audiocarrier of the received video signal. Circuit 11 supplies theprogrammable divider circuit, with a suitable modified number N and thistuning condition is automatically associated in the memory with key "0".Operation is similar when key "-" is pressed except for the direction ofthe tuning adjustment (towards the video). Once nominal tuning isobtained, the "+" sign and the following number are cancelled while, formore defective tuning conditions, the "-" sign appears followed by thenumber of displacements made. The system is so designed to limit maximumvariations to the -16 to +15 range. Of course, the tuning correction canbe made in the same way even with the set in the direct selection mode(mode "C").

In this case though the operation does not involve automaticmemorization. For the channel and obtained tuning condition to bememorized, the "M" key must be pressed, followed by a number key.

When the "CT" (keyboard switch) key is pressed, the display shows:

    ______________________________________                                                  OO:MM:SS *T*                                                                  CHANNEL  21+01                                                                KEY  O                                                              ______________________________________                                    

This tells the user ("*" beside the mode indication) that the device isset to perform a further series of functions corresponding to the secondindication on each key. Following this operation, the processing circuit11 supplies character generator 16 with a switch signal to switch thecolor of the writing on the screen or the background color so as to makeit even more clear to the user that the controls available from thattime on correspond to second key indications (this applies, of course,to color television sets).

If one of the keys marked "A" to "L" is pressed, the display shows:

    ______________________________________                                                  OO:MM:SS   *C*                                                                CHANNEL    A                                                        ______________________________________                                    

This tells the user that the television is set to mode "C" but, in thiscase, channels can be selected directly according to the Italianstandard by pressing a single key with indication of the receivedchannel.

When one of keys R1, R2, R3 or R4 is pressed, the display shows, forexample:

    ______________________________________                                                  OO:MM:SS  *1*                                                                 CHANNEL   21+01                                                               KEY       O  RA                                                     ______________________________________                                    

This tells the user that the set is performing an automatic scanningoperation, for example type 1, or is scanning all the channels in thememory.

Scanning progresses automatically every two seconds with indications ineach case of the key number and associated channel. At the same time,processing circuit 11 generates the relative N numbers for receiving thechannel. Scanning stops when any other key is pressed. If the "+" or "-"key is pressed, the device remains set for manual advance or reversing(every time the "+" key is pressed, the key number is increased anddecreased every time the "-" key is pressed). If the "CT" key ispressed, the device switches back to the first keyboard and awaitsfurther instructions, in particular, tuning correction or memorizationcontrols. Similarly, if key R2 is pressed after selecting the secondkeyboard using the "CT" key, this starts a type 2 scanning operation ofall the standard channels (one switch per second). This can be stoppedin the same way as type 1 scanning.

If key R3 is pressed, this starts a continuous scanning operation of thefrequency band in 1 MHz steps, that is, 4 fine tuning switches persecond, to detect any emitters operating over non-standard frequencies.The same type of scanning operation, though at reduced speed (one switchevery two seconds), is started pressing key R4.

The "KEY" indication is not displayed during type 2, 3 and 4 scanningoperations.

Display or omission of the fixed "CHANNEL" and "KEY" indications dependson whether the indication or blank sectors of the ROM memory areutilized. Circuit 11 also comprises a timer which, 15 seconds after thelast key has been activated, supplies a switch signal (bit 6 port 1) tocharacter generator 16 which reduces the display to one line and alsohalves the height of the characters (7 instead of 14 television lines)to reduce disturbance to the picture. This switch signal, of course, isnot supplied during automatic scanning or clock adjustment.

To prevent memorized data being lost during a power cut, provision ismade for a battery-supplied outside RAM memory 12. Whenever memorizationoperation is performed, processing unit 11 updates the information inthe RAM memory. When power supply returns to normal, the same unit 11calls up the data memorized in the RAM memory. "ON RESET" circuit 15 andcombiner circuit 14 protect the data contained in RAM memory 12 duringtransient states between power supply failure and restoration.

Operation of processing unit 11 is shown more clearly in the elementarylogic function block diagrams in FIGS. 2, 3 and 4.

FIG. 2 shows operation mode and relative indication selection;

FIG. 3 shows updating of the data in outside RAM memory 12;

FIG. 4 shows data being called up from the outside RAM memory followingrestoration of the power supply.

Number 20 in FIG. 2 indicates a timer which sets a switch circuit, 22,with its output usually towards block 23 and supplies an RTI signal toblock 21 which reads the controls set on the keyboard. Block 21, viaswitch 22, supplies a signal to block 23 which ascertains the presenceof a new order. The "NO" output supplies the RTI signal whichreactivates reading block 21 while the "YES" output activates block 24which ascertains whether the key pressed was a mode key. The "NO" outputof block 24 activates block 25 which examines the operation modeselected and, in turn, activates block 26 which, depending on the modechosen, combines and supplies the indication sequence to the charactergenerator for display. Block 26 then activates block 27 which examinesthe number keys pressed and activates block 28 which ascertains whetherthe corresponding order is feasible.

The "NO" output of the said block 28 (control not feasible, e.g. thenumber does not correspond to a standard number channel) activates afollowing block 34 which inserts question marks at appropriate points inthe buffer to inform the user that the control is not feasible andtransmits them to character generator 16 (FIG. 1). Block 34 thensupplies an RTI signal to block 21 which reads the keyboard once moreawaiting further instructions.

The "YES" output of block 28 activates block 29 which sends the channelor key members to the buffer, usually the numbers of the order received,transmits the numbers to the character generator and, finally, activatesblock 30 which calculates number N according to equation (3) and sendsthis number to programmable divider 4 (FIG. 1) to obtain the requiredtuning. Finally, block 30 supplies the RTI signal to block 21.

The "YES" output of block 24 activates block 36 which inserts theindications and question marks in the buffer and transmits them to thecharacter generator (as described already). Block 36 then supplies block21 with the RTI signal. After a set length of time (about 4milliseconds), depending on circuit 20, switch 22 positions itself withits output towards count circuit 31 which, after a set number of pulses(about 250) per second, supplies a signal to block 32 which updates theclock numbers in the buffer and activates block 33 which sends the datacontained in the buffer to the character generator and then supplies anRTI signal to block 21. Number 40 in FIG. 3 indicates a block forascertaining whether the operation selected involves memorization. The"NO" output supplies a signal which activates block 25 (FIG. 2) whilethe "YES" output activates in turn:

block 41, which examines the number of the key pressed;

block 42, which memorises the channel number and tuning in the registerscorresponding to the said key;

block 43, which supplies an enabling signal (C.E.) and a first addressfor the outside memory circuit 12;

block 44, which supplies the channel number data and a memorizing pulse(WRITE) to the same circuit 12;

block 45, which supplies the new address;

block 46, which supplies the tuning data and memorizing pulse to memory12.

Number 50 in FIG. 4 indicates a block which, following an "ON RESET"signal from circuit 15 in FIG. 1, supplies an output enabling (O.E.)signal to memory 12 as well as a signal for activating in turn:

block 51, which supplies the address to memory 12;

block 52, which reads the data from memory 12 and loads it into theregisters in unit 11 of FIG. 1;

block 53, which calculates the new address;

block 54, which ascertains whether all the cells in memory 12 have beenread.

The "NO" output of block 54 supplies a signal for activating block 51once more. The "YES" output activates block 55 which sets to mode "T"(memory selection) and key "O" and supplies an activation signal toblock 25 of FIG. 2.

For further information concerning operation of the device, refer toItalian Patent Application n. 69950-A/77, already mentioned, whichdescribes a device partly similar to the present one. On the actualdevice, a Fairchild F8 microprocessor unit was chosen for processingunit 11 which consists of a 3850 C.P.U., 3861 P.I.O., 3853 S.M.I. andtwo PROM F93448 memories. Each of the said two PROM memories consistsessentially of a connection matrix with a 512×8 format, input andaddress decoding circuits and output buffer circuits.

Each connection may be open or closed and represents permanentelementary data (bit) 1 or 0 respectively. Each group of 8 connections,addressed by one of the 512 address input combinations, represents anelementary 8-bit instruction or word (byte). By applying all thepossible address combinations at the input, all the data contained inthe ROM can be obtained at the output in word form.

These connections are described in the following tables for the circuit.The left-hand columns show the addresses, using hexadecimal notation,and the right-hand ones the connections of the corresponding memorycell. Number 1 refers to an open connection with logic 1 at the outputwhile 0 refers to a closed connection.

As each memory cell consists of 8 connections, this means it can berepresented with a combination of 8 binary figures. For the sake ofsimplicity, the hexadecimal system was used on the following tables, sothat, for example, EA for base 16, which corresponds to 11101100 of base2, indicates that the corresponding memory cell has connections 1, 2, 3,5 and 6 open and the rest closed.

                  TABLE 1                                                         ______________________________________                                        ADDRESS     CODE       ADDRESS     CODE                                       ______________________________________                                        0000        70         000C        04                                         0001        B5         000D        6A                                         0002        B1         000E        7A                                         0003        B6         000F        5C                                         0004        BE         0010        6D                                         0005        BF         0011        5C                                         0006        B4         0012        7F                                         0007        65         0013        58                                         0008        6F         0014        18                                         0009        5E         0015        07                                         000A        8F         0016        67                                         000B        FE         0017        5C                                         0018        66         0031        70                                         0019        5E         0032        BD                                         001A        8F         0033        5B                                         001B        FE         0034        B5                                         001C        20         0035        90                                         001D        10         0036        12                                         001E        0B         0037        1B                                         001F        24         0038        A5                                         0020        90         0039        EB                                         0021        B5         003A        84                                         0022        A4         003B        FD                                         0023        5C         003C        59                                         0024        0A         003D        21                                         0025        1F         003E        10                                         0026        25         003F        49                                         0027        28         0040        94                                         0028        94         0041        19                                         0029        F5         0042        EB                                         002A        7C         0043        5B                                         002B        06         0044        91                                         002C        15         0045        F3                                         002D        5A         0046        73                                         002E        B1         0047        BE                                         002F        72         0048        1A                                         0030        BC         0049        67                                         004A        4B         0063        03                                         004B        21         0064        66                                         004C        1F         0065        6B                                         004D        59         0066        5C                                         004E        6F         0067        69                                         004F        25         0068        5C                                         0050        09         0069        29                                         0051        81         006A        02                                         0052        1A         006B        06                                         0053        25         006C        47                                         0054        0F         006D        56                                         0055        81         006E        49                                         0056        32         006F        57                                         0057        29         0070        5E                                         0058        02         0071        46                                         0059        03         0072        5D                                         005A        1A         0073        E8                                         005B        EB         0074        84                                         005C        5B         0075        1D                                         005D        21         0076        66                                         005E        10         0077        6A                                         005F        20         0078        00                                         0060        FA         0079        CC                                         0061        94         007A        91                                         0062        02         007B        17                                         007C        7F         0095        25                                         007C        5C         0096        0D                                         007E        6E         0097        84                                         007F        03         0098        0A                                         0080        5D         0099        81                                         0081        5C         009A        23                                         0082        67         009B        25                                         0083        5E         009C        0F                                         0084        8F         009D        84                                         0085        FE         009E        40                                         0086        90         009F        29                                         0087        E2         00A0        01                                         0088        25         00A1        3B                                         0089        0B         00A2        67                                         008A        81         00A3        6C                                         008B        51         00A4        03                                         008C        06         00A5        5C                                         008D        03         00A6        7D                                         008E        5E         00A7        66                                         008F        5D         00A8        6A                                         0090        7F         00A9        06                                         0091        5E         00AA        55                                         0092        02         00AB        20                                         0093        67         00AC        10                                         0094        6F         00AD        52                                         00AE        20         00C7        E4                                         00AF        D3         00C8        5C                                         00B0        5C         00C9        67                                         00B1        47         00CA        6C                                         00B2        E8         00CB        47                                         00B3        94         00CC        5C                                         00B4        03         00CD        E8                                         00B5        57         00CE        84                                         00B6        56         00CF        9A                                         00B7        46         00D0        47                                         00B8        15         00D1        13                                         00B9        C7         00D2        24                                         00BA        51         00D3        10                                         00BB        90         00D4        0B                                         00BC        1D         00D5        4D                                         00BD        55         00D6        51                                         00BE        03         00D7        4C                                         00BF        5E         00D8        52                                         00C0        8F         00D9        29                                         00C1        FE         00DA        01                                         00C2        66         00DB        84                                         00C3        5E         00DC        90                                         00C4        5C         00DD        4A                                         00C5        6A         00DE        66                                         00C6        20         00DF        4C                                         00E0        E8         00F9        13                                         00E1        84         00FA        B5                                         00E2        35         00FB        05                                         00E3        67         00FC        24                                         00E4        20         00FD        10                                         00E5        DD         00FE        0B                                         00E6        5C         00FF        72                                         00E7        6B         0100        59                                         00E8        4D         0101        41                                         00E9        CE         0102        5D                                         00EA        1F         0103        B4                                         00EB        84         0104        01                                         00EC        2B         0105        EA                                         00ED        20         0106        B5                                         00EE        F3         0107        EA                                         00EF        5D         0108        B5                                         00F0        47         0109        1F                                         00F1        5C         010A        B5                                         00F2        E8         010B        05                                         00F3        84         010C        42                                         00F4        31         010D        5C                                         00F5        A1         010E        39                                         00F6        EA         010F        94                                         00F7        B1         0110        F3                                         00F8        4C         0111        70                                                                0112        B4                                         0113        B5         012C        52                                         0114        A1         012D        6B                                         0115        EA         012E        4E                                         0116        B1         012F        C8                                         0117        70         0130        81                                         0118        57         0131        55                                         0119        45         0132        6C                                         011A        06         0133        70                                         011B        03         0134        CC                                         011C        67         0135        81                                         011D        6F         0136        BC                                         011E        5E         0137        70                                         011F        5C         0138        57                                         0120        6C         0139        90                                         0121        4C         013A        4A                                         0122        E8         013B        49                                         0123        94         013C        23                                         0124        60         013D        0E                                         0125        90         013E        94                                         0126        5B         013F        1E                                         0127        13         0140        20                                         0128        18         0141        E2                                         0129        24         0142        5E                                         012A        16         0143        20                                         012B        C2         0144        DF                                         0145        5C         015E        E8                                         0146        6B         015F        84                                         0147        4C         0160        21                                         0148        C8         0161        46                                         0149        91         0162        25                                         014A        04         0163        05                                         014B        03         0164        91                                         014C        5D         0165        0C                                         014D        5C         0166        00                                         014E        65         0167        24                                         014F        68         0168        03                                         0150        4A         0169        04                                         0151        04         016A        24                                         0152        7F         016B        65                                         153         5D         016C        0B                                         0154        5C         016D        46                                         0155        6B         016E        5D                                         0156        5D         016F        47                                         0157        5C         0170        5C                                         0158        6E         0171        7F                                         0159        5D         0172        57                                         015A        5D         0173        68                                         015B        90         0174        4D                                         015C        25         0175        15                                         015D        46         0176        CC                                         0177        25         0190        53                                         0178        23         0191        41                                         0179        91         0192        05                                         017A        D4         0193        25                                         017B        90         0194        01                                         017C        05         0195        81                                         017D        7F         0196        E7                                         017E        66         0197        25                                         017F        5E         0198        79                                         0180        5C         0199        91                                         0181        29         019A        E3                                         0182        02         019B        F8                                         0183        06         019C        25                                         0184        67         019D        09                                         0185        6B         019E        91                                         0186        03         019F        DE                                         0187        5E         01A0        70                                         0188        8F         01A1        CE                                         0189        FE         01A2        91                                         018A        66         01A3        04                                         018B        5E         01A4        03                                         018C        5D         01A5        5D                                         018D        67         01A6        5E                                         018E        70         01A7        66                                         018F        50         01A8        41                                         01A9        25         01C3        C9                                         01AA        69         01C4        51                                         01AB        81         01C5        25                                         01AC        0B         01C6        14                                         01AD        F8         01C7        91                                         01AE        2A         01C8        4A                                         01AF        03         01C9        13                                         01B0        E0                                                                01B1        8E         01CA        C1                                         01B2        24         01CB        13                                         01B3        02         01CC        C1                                         01B4        51         01CD        59                                         01B5        16         01CE        01                                         01B6        53         01CF        25                                         01B7        41         01D0        69                                         01B8        14         01D1        81                                         01B9        5D         01D2        07                                         01BA        13         01D3        03                                         01BB        59         01D4        5D                                         01BC        13         01D5        79                                         01BD        13         01D6        8E                                         01BE        C9         01D7        16                                         01BF        59         01D8        5E                                         01C0        41         01D9        41                                         01C1        F8         01DA        25                                         01C2        5E         01DB        04                                         01DC        20         01EE        00                                         01DD        45         01EF        38                                         01DE        81         01F0        29                                         01DF        05         01F1        00                                         01E0        74         01F2        37                                         01E1        50         01F3        29                                         01E2        20         01F4        00                                         01E3        AF         01F5        48                                         01E4        C3         01F6        29                                         01E5        90         01F7        00                                         01E6        2A         01F8        A2                                         01E7        FF         01F9        29                                         01E8        FF         01FA        00                                         01E9        FF         01FB        C9                                         01EA        FF         01FC        29                                         01EB        FF         01FD        01                                         01EX        FF         01FE        84                                         01ED        29         01FF        FF                                         ______________________________________                                    

                  TABLE 2                                                         ______________________________________                                        ADDRESS     CODE       ADDRESS     CODE                                       ______________________________________                                        0200        29         0203        29                                         0201        02         0204        03                                         0202        DD         0205        26                                         0206        29         0220        20                                         0207        02         0221        52                                         0208        7A         0222        C9                                         0209        FF         0223        51                                         020A        FF         0224        40                                         020B        FF         0225        19                                         020C        FF         0226        13                                         020D        FF         0227        13                                         020E        FF         0228        50                                         020F        FF         0229        70                                         0210        90         022A        C2                                         0211        11         022B        81                                         0212        20         022C        04                                         0213        20         022D        70                                         0214        C1         022E        90                                         0215        51         022F        07                                         0216        13         0230        25                                         0217        13         0231        20                                         0218        13         0232        81                                         0219        59         0233        03                                         021A        41         0234        20                                         021B        14         0235        20                                         021C        12         0236        52                                         021D        24         0237        41                                         021E        08         0238        14                                         021F        50                                                                0239        12         0252        72                                         023A        12         0253        C9                                         023B        C0         0254        18                                         023C        50         0255        B0                                         023D        41         0256        01                                         023E        13         0257        51                                         023F        13         0258        67                                         0240        C2         0259        68                                         0241        59         025A        03                                         0242        40         025B        C2                                         0243        19         025C        84                                         0244        18         025D        1D                                         0245        B1         025E        50                                         0246        01         025F        20                                         0247        25         0260        FB                                         0248        70         0261        5C                                         0249        84         0262        81                                         024A        08         0263        08                                         024B        25         0264        20                                         024C        74         0265        FD                                         024D        84         0266        5C                                         024E        04         0267        40                                         024F        70         0268        18                                         0250        90         0269        1F                                         0251        02         026A        50                                         026B        20         0284        25                                         026C        67         0285        C9                                         026D        59         0286        91                                         026E        70         0287        12                                         026F        D9         0288        84                                         0270        30         0289        04                                         0271        94         028A        29                                         0272        FD         028B        01                                         0273        69         028C        ED                                         0274        59         028D        45                                         0275        14         028E        06                                         0276        5D         028F        70                                         0277        49         0290        57                                         0278        F8         0291        20                                         0279        5C         2092        FD                                         027A        7F         0293        54                                         027B        53         2094        03                                         027C        A1         0295        67                                         027D        22         0296        6F                                         027E        40         0297        5E                                         027F        B1         0298        5C                                         0280        28         0299        29                                         0281        02         029A        01                                         0282        9C         029B        F0                                         0283        00         029C        2A                                         029D        03         02B6        CC                                         029E        D0         02B7        81                                         029F        20         02B8        03                                         02A0        80         02B9        7A                                         02A1        B4         02BA        8E                                         02A2        65         02BB        66                                         02A3        68         02BC        6E                                         02A4        74         02BD        4C                                         02A5        59         02BE        24                                         02A6        7C         02BF        30                                         02A7        50         02C0        18                                         02A8        16         02C1        B4                                         02A9        B4         02C2        CA                                         02AA        CA         02C3        B4                                         02AB        B4         02C4        0A                                         02AC        39         02C5        1F                                         02AD        94         02C6        0B                                         02AE        FA         02C7        30                                         02AF        0A         02C8        94                                         02B0        25         02C9        F4                                         02B1        34         02CA        CA                                         02B2        94         02CB        84                                         02B3        0A         02CC        07                                         02B4        67         02CD        7B                                         02B5        70         02CE        59                                         02CF        75         02E7        20                                         02D0        50         02E8        67                                         02D1        90         02E9        DC                                         02D2        D6         02EA        5E                                         02D3        B4         02EB        14                                         02D4        33         02EC        CC                                         02D5        81         02ED        5D                                         02D6        06         02EE        25                                         02D7        53         02EF        05                                         02D8        A1         02F0        81                                         02D9        21         02F1        1C                                         02DA        BF         02F2        70                                         02DB        B1         02F3        5E                                         02DC        1C         02F4        5C                                         02DD        34         02F5        6C                                         02DE        94         02F6        39                                         02DF        41         02F7        94                                         02E0        72         02F8        EF                                         02E1        59         02F9        69                                         02E2        20         02FA        20                                         02E3        FE         02FB        67                                                                02FC        DC                                         02E4        54         02FD        5E                                         02E5        65         02FE        14                                         02E6        6F         02FF        CC                                         0300        5D         0319        20                                         0301        25         031A        F3                                         0302        01         031B        91                                         0303        81         031C        05                                         0304        09         031D        28                                         0305        4C         031E        02                                         0306        25         031F        9C                                         0307        03         0320        03                                         0308        81         0321        05                                         0309        04         0322        71                                         030A        70         0323        04                                         030B        5E         0324        1B                                         030C        5D         0325        0C                                         030D        4C         0326        4B                                         030E        F8         0327        F8                                         030F        5C         0328        06                                         0310        6F         0329        25                                         0311        4C         032A        09                                         0312        21         032B        81                                         0313        01         032C        62                                         0314        CB         032D        03                                         0315        21         032E        6C                                         0316        1F         032F        5C                                         0317        25         0330        6F                                         0318        1C         0331        5E                                         0332        20         034B        5C                                         0333        E2         034C        25                                         0334        5D         034D        02                                         0335        02         034E        84                                         0336        13         034F        11                                         0337        18         0350        91                                         0338        24         0351        28                                         0339        16         0352        47                                         033A        25         0353        C0                                         033B        FE         0354        81                                         033C        91         0355        02                                         033D        08         0356        79                                         033E        02         0357        25                                         033F        55         0358        09                                         0340        20         0359        81                                         0341        D1         035A        02                                         0342        5C         035B        70                                         0343        71         035C        57                                         0344        04         035D        29                                         0345        50         035E        01                                         0346        66         035F        F9                                         0347        6A         0360        20                                         0348        45         0361        10                                         0349        24         0362        52                                         034A        F5         0363        70                                         0364        C0         037D        81                                         0365        91         037E        05                                         0366        03         037F        20                                         0367        24         0380        1C                                         0368        66         0381        90                                         0369        D1         0382        E0                                         036A        25         0383        25                                         036B        01         0384        1C                                         036C        92         0385        81                                         036D        03         0386        04                                         036E        20         0387        70                                         036F        79         0388        90                                         0370        25         0389        D9                                         0371        79         038A        52                                         0372        81         038B        41                                         0373        02         038C        90                                         0374        72         038D        DD                                         0375        51         038E        57                                         0376        29         038F        77                                         0377        01         0390        56                                         0378        FC         0391        5C                                         0379        40         0392        29                                         037A        13         0393        01                                         037B        13         0394        F6                                         037C        C2                                                                03B0        DF         03C9        DF                                         03B1        CE         03CA        C7                                         03B2        EF         03CB        FE                                         03B3        DF         03CC        DF                                         03B4        DF         03CD        DF                                         03B5        CA         03CE        DF                                         03B6        ED         03CF        DF                                         03B7        DF         03D0        DF                                         03B8        FC         03D1        DF                                         03B9        FE         03D2        DF                                         03BA        F1         03D3        DF                                         03BB        FE         03D4        FF                                         03BC        F3         03D5        FF                                         03BD        FA         03D6        FF                                         03BE        DF         03D7        FF                                         03BF        DF         03D8        FF                                         03C0        C7         03D9        FF                                         03C1        FE         03DA        FF                                         03C2        DF         03DB        FF                                         03C3        EB         03DC        FF                                         03C4        FE         03DD        FF                                         03C5        EC         03DE        FF                                         03C6        EB         03DF        FF                                         03C7        F0         03E0        05                                         03C8        DF         03E1        07                                         03E2        14         03EB        D2                                         03E3        00         03EC        D3                                         03E4        01         03ED        D4                                         03E5        03         03EE        D5                                         03E6        05         03EF        D6                                         03E7        07         03F0        D7                                         03E8        07         03F1        D8                                         03E9        07         03F2        D9                                         03EA        D1         03F3        DC                                         ______________________________________                                    

The above tables contain, in coded form, one possible sequence ofelementary operations for performing, via the microprocessor systemindicated, the functions shown in the block diagrams and foregoingdescription.

FIG. 5 shows a more detailed representation of the block diagram ofcharacter generator 16 in FIG. 1.

Number 60 in FIG. 5 indicates a character count circuit for supplyingthe addresses to character memory 61. This has a 48×6 format forcontaining the 48 characters transmitted periodically by processing unit11.

The six INPUT/OUTPUT terminals of the said memory are connected to sixoutput terminals of PORT 71 of processing unit 11. These are alsoconnected to six inputs of character ROM 62.

This may be a Fairchild 3258 type, for memorizing 64 characters for eachof which it supplies an image consisting of a 5×7 point matrix. Eachcharacter is separated vertically from the next by two lines of blanks.

A built-in counter, which receives a clock signal with horizontalscanning frequency FH from the television circuits and a reset signal R1from circuit 60, scans the following point lines of the said matrix.

The five outputs of the said ROM 62 are connected to a parallel-seriesconverter circuit 63 which transforms the 5 signals received from thesaid 5 outputs into a series signal. It also adds a suitable number ofblanks (e.g. 3) on to the end of the said 5 signals to separate thecharacters horizontally.

Circuit 63 receives a clock signal from oscillator circuit 66 thefrequency of which determines the width of each of the charactersdisplayed on the screen. It also receives a LOAD signal "L" for eachcharacter (every 5+3=8 clock cycles in the example shown) from dividercircuit 67 which, in turn, receives the clock signal from oscillatorcircuit 66. The signal thus appearing at the output of converter 63 issent to combiner circuit 64 consisting of known logic elements (e.g.three 2-input AND gates each with a first input connected to the outputof circuit 63 and a second connected to one of the outputs of circuit65) which sends the said signal to one or more of its three outputs,marked R, G and B in the Figure, in response to the same number ofcontrol signals supplied by control circuit 65. The said outputs R, Gand B are connected, in the known way, to the amplifier circuits of thecolor signals on the set so that the signals supplied by circuit 64 areadded to the video ones of the received television signal.

Depending on the instructions received from circuit 65, it is possibleto obtain the indications in any one of the three primary colorcombinations.

In FIG. 5, the control circuit 65 receives a control signal from anoutput of circuit 71-port 4 of unit 11-(FIG. 1) so that the indicationsare displayed in green when the system is set to the first keyboard andyellow when it is set to the second.

Numbers 68, 69 and 70 indicate three switch circuits, similar to oneanother, controlled in parallel by a control signal DT supplied by a bitof port 1 of processing unit 11 in FIG. 1. Depending on the DT signal,these three switch circuits enable the FIG. 5 circuits to be set so asto load the data in memory 61 when the DT signal is present (high) and,vice versa, to set the same circuits for transmitting the data from thesaid memory to outputs R, G and B when the DT signal is absent (low) orwhen unit 11 is not transmitting characters to memory 61 (for displayupdating). To do this, when the DT signal is present, switches 68, 69and 70 are positioned as shown by letter A in FIG. 5. This causes areset pulse to be applied to terminals R2 and R3 of count circuit 60 andmemory 61 is set to INPUT by the same DT signal applied to theinput-output I/O control terminal.

Count circuit 60 receives clock pulses DC from an output terminal ofprocessing unit 11 of FIG. 1 (port 4) via switch circuit 68. The same DCsignal is also applied to the write control input "W" of memory 61.

In this way, for each clock pulse it receives, counter 60 supplies RAMmemory 61 with addresses 0 to 47. At the same time, unit 11 supplies the48 signals (at port 4) received at the data input of the same memory sothat they are memorized in the corresponding cells as a result of the"W" pulses.

When the DT signal is absent, on the other hand, (switches in positionB), character counter 60 receives clock signals from circuit 66 viadivider 67, reset signals with vertical scanning frequency FV atterminal R2, reset signals with horizontal scanning frequency FH atterminal R3 and a formatchange signal "F" from processing unit 11. Inthis way, it supplies memory 61 with suitable addresses for arrangingthe 48 display characters in three 16-character lines, should signal "F"be present, or else it supplies the said memory with only the firstsixteen addresses for displaying a single 16-character line when signal"F" is absent. Counter 60 also supplies combiner circuit 64 with adisabling circuit for deactivating it during the remaining televisionpicture time. In this way, only a certain part of the screen isdisplayed, e.g. the top left-hand corner. If needed, the same disablingsignal can be used for supplying a blank signal at an appropriate pointin the television video amplification chain so as to blacken thebackground of the display to make the characters more visible.

A further output of circuit 71 (port 4 of unit 11) controls a switch,72, between a BIP signal (which can be picked up at an appropriate pointon the circuit, e.g. at the output of divider 7 of FIG. 1) and a firstinput of an adding circuit, 73, whose second input receives the audioB.F. signal of the received television signal picked up downstream fromthe manual volume adjuster. The output of the said adding circuit isconnected to the input of the B.P. amplifier, 74, on the set whichpilots the loudspeaker 75. In this way, under given circumstances, theprocessing unit 11 can control the sounding of an alarm for warning theuser. The said circumstances may be:

when the "M" memory key is pressed. The alarm reminds the user that thekey has been pressed so as to prevent him from altering the content ofthe memory by mistake;

when an unperformable instruction is given (e.g. the number of anon-existent channel or time) etc.

when the maximum allowable limits have been reached for certainadjustments such as fine tuning corrections.

FIG. 6 gives a more detailed view of parts of circuits 12, 13, 14 and 15in FIG. 1 showing memorization of the channels in the outside memory andmaintenance of data during temporary power cuts. The said circuits 12,13, 14 and 15 roughly correspond to the blocks marked 113, 100, 105 and80 in FIG. 6.

Block 80 comprises a Zener diode, 83, connected between a +12 output ofa supply circuit ("AC" voltage input, transformer 81 and rectifier 82)and a grounded resistor 84. The signal present at the resistor terminalsis sent to an integrator circuit consisting of resistor 86, diode 87 andcondenser 85.

The signal made available here, and inverted by inverter 88, is sent toinverter circuit 95 via integrator assembly consisting of resistor 93and condenser 94, and also to the base of common-emitter transistor 90via coupling resistor 89. The collector of transistor 90 is connected toa +5 supply voltage through resistor 92 and grounded through push-buttonswitch 91 and supplies a reset signal to processing unit 11 (FIG. 1).

The +12 voltage is also supplied to the input of a stabilizer circuit 96at the output of which, filtered by condenser 97, is made available the+5 supply voltage for supplying other circuits not shown in the Figure.The output of inverter 95 is connected to a first input of NAND gates107 and 109 and to both inputs of NAND gate 106 which acts as aninverter. The output of the said gate 106 is connected to a reset inputR4 of separator circuit 112 which receives the output signal of gate 107at its disabling input C.D. via inverter circuit 110. Gate 107 receivesa conditioning signal C.S. from processing unit 11 of FIG. 1 at itssecond input. The output of gate 107 is also connected to a deactivatinginput C.D. of memory 113. A READ signal from processing unit 11 of FIG.1 is sent via NAND gate 108, which acts as an inverter, to the readdisabling "NR" input of memory 113. This input is also connected to asecond input of gate 109 the output of which is connected to a writedisabling "NW" input of the same memory 113.

The +5 voltage is also supplied to the anode of diode 101 at the cathodeof which is connected a condenser, 104, the second terminal of which isgrounded. Resistor 102 and 3 Volt battery 103, connected in series, arealso connected parallel to condenser 104. The voltage available at theterminals of condenser 104 supplies memory 113, separator 112 and the 4gates 106, 107, 108 and 109 contained in a single semiconductor body(CHIP).

Separator 112 has 5 inputs connected to 5 outputs of control circuit 111(keyboard or remote-control receiver) and 5 outputs connected to 5terminals of circuit 114 (port 5 of processing unit 11 in FIG. 1).

The same 5 outputs are also connected to 5 address inputs of memory 113.

The circuit described above operates as follows:

The function of block 100 is to generate a permanent supply voltage tokeep memory 113 activated. In the event of a power cut, battery 103supplies sufficient current to maintain the data in the memory throughresistor 102. Vice versa, when power is being supplied from the mains,the +5 voltage is supplied to the memory via diode 101 and, at the sametime, the battery is recharged slightly through resistor 102.

By means of Zener diode 83 and the integrator circuit comprisingelements 85, 86 and 87, block 80 supplies a signal, at the output ofinverter 95, after the +5 voltage, when the power supply is restored,and in advance of the said voltage when the power supply is cut off. Inthis way, the signals supplied by processing unit 11 to memory 113cannot reach the memory during a power cut or during transient states.

Under the above conditions, gates 107, 108 and 109 are conditioned so asto protect memory 113 whereas gates 106 and 110 force separator 112 tosupply a series of zeros at the output to prevent the memory fromreceiving chaotic address signals.

Block 80 also supplies, at the output of transistor 90, a signal similarto the one supplied by inverter 95 to keep processing unit 11 inactiveduring transient states and thus prevent uncontrolled operation.Push-button 91, however, enables a reset signal to be supplied manuallyto the said unit to commence the operation sequence from a preset point.

FIG. 7 shows a possible variation of one part of the circuit shown inFIG. 1. FIG. 7 only illustrates the parts which differ from FIG. 1 orwhich are connected differently.

Number 120 in FIG. 7 indicates a control keyboard which, besides thekeys shown in FIG. 1 and not repeated here, comprises 6 keys marked"V+", "V-", "L+", "L-", "C+" and "C-". The outputs of the said keyboardare connected to a group of input-output terminals 5 of processing unit121 which is essentially the same as unit 11 in FIG. 1 from which itdiffers, among other things, by the provision of a further group ofoutput terminals (ports) 6.

Six terminals of the said group are connected to six inputs of adigital/analogue converter 123 of the known type (e.g. consisting of aknown network of R/2R resistors). The analogue output of the saidconverter is supplied to a switch circuit 124 with three outputs markedV, L and C in the Figure which are connected to three storage condensers125, 126 and 127 respectively. Switch 124 also has two control inputterminals connected to the remaining two output terminals of port 6 ofunit 121 which receive the respective control signals for forwarding theanalogue signal to one or other of condensers 125, 126 or 127.

The group of terminals or port 4 is connected to 8 input/outputterminals of a RAM memory circuit 122. This replaces memory 12 of FIG. 1from which it differs by the number of 8-bit cells (10×5 instead of10×2). This memory also receives six address bits (instead of 5) fromsix output terminals (port 5) of unit 121.

The FIG. 7 circuit operates as follows:

When one of the six keys mentioned above is pressed (e.g. key "V+"),unit 121 supplies the character generating circuit with a combination ofsymbols which may be:

VVVVVVVV . . .

LLLLLL . . .

CCCCCCCCCCC . . .

The line of symbols corresponding to the pressed key (V, L, C) isdisplayed with a different color from the rest. The number of charactersper line is proportional to the corresponding analogue signal level (V,L, C) at that time. Whenever one of the + keys is pressed, thecorresponding analogue level is increased 1/64 of maximum value. When anoperation involving memorization is performed (e.g. whenever "KEY"operation mode is adjusted or the "M" key pressed), processing unit 121transmits the relative data in digital form to memory 122 and has itmemorized with much the same procedure already described and shown inFIG. 3. This means the data memory 122 is called upon to memorize foreach of the 10 "KEYS" is of 5 types: channel, tuning, volume, brightnessand color. For the sake of uniformity; the memory accepts 8-bit datawhereas, for analogue adjustments, 6 bits (64 levels) are more thanenough so two bits are ignored.

Other ways exist of displaying analogue levels on the television screenusing the character generator and circuit arrangement described in thepresent invention. Besides the one described above, the display couldshow any one of the following:

    ______________________________________                                                  V*******                                                                              <                                                                     L*****                                                                        C**********                                                                   or :                                                                          VOLUME  40    ?                                                               BRIGHTNESS                                                                              30                                                                  colour  50                                                                    or :                                                                          V+++++                                                                        L                                                                             C--                                                                 ______________________________________                                                   In the first, the number of asterisks is proportional to the     relative analogue signal level and the adjustment being made indicated by     the symbol ">". In the second, the level is indicated by the number to the     side of the adjustment item while the adjustment being made is indicated     by the question mark. In the third, the number of "+" (or "-") signs is     proportional to the increase (or decrease) made to the preset nominal     level. Of course, the preselected, memorized levels are preserved in     memory 122, even in the event of a power cut, thanks to the precautions     already described which also apply to the FIG. 7 case.

It may prove useful to apply the sound alarm described in FIG. 5 foranalogue adjustments too, for example, when the maximum level isreached.

The advantages of the present invention will be clear from the foregoingdescription. However, a number of variations can be made. For example,in the description, it was supposed a particular type of 8-bitmicroprocessor system was used with a separate CPU and ROM. It ispossible, and even convenient, to use other types of microprocessorswith a higher number of internal RAM registers (e.g. 128) or a so-calledmonochip containing an internal RAM and timer circuit, besides the ROM,or a 16-bit microprocessor. It may even prove useful to fit the receiverwith a remote-control. In this case, a keyboard similar to the onedescribed is combined on the portable transmitter part of theremote-control system. A further variation, to avoid duplicating thecontrol keyboard, could be to provide accommodation in the receiverhousing with electric contacts in which to connect the transmitter partfor operating the local control.

Many other variations can be made without, however, departing from thescope of the present invention.

For example, besides the key arrangement in FIG. 1 for controllingchannel selection or FIG. 7 for controlling analogue levels (V, L, C), anumber of different combinations can be used even using other controlcomponents different from keys or push-buttons.

I claim:
 1. A television set, comprising:a picture display device fordisplaying a video picture; character generator means for generatingsignals representative of alphabetical, numerical and/or abstractcharacters; said picture display device receiving said signals anddisplaying the alphabetical, numerical and/or abstract charactersrepresented thereby; and control means for determining the value ofanalog data, other than the tuning frequency of said television set,relating to the operation of said television set, and for causing saidcharacter generator means to generate signals representative ofalphabetical, numerical and/or abstract characters which indicate saidvalue of said analog data.
 2. A television set, comprising:a picturedisplay device for displaying a video picture; character generator meansfor generating signals representative of alphabetical, numerical and/orabstract characters; said picture display device receiving said signalsand displaying the alphabetical, numerical and/or abstract charactersrepresented thereby; and control means for determining the value ofanalog data relating to the operation of said television set and forcausing said character generator means to generate signalsrepresentative of alphabetical, numerical and/or abstract characterswhich indicate said value of said analog data, said control means alsocausing said character generator means to generate signalsrepresentative of alphabetical, numerical and/or abstract charactersindicative of which of said data the user of said television set haslast selected to adjust.
 3. A television set, comprising:a picturedisplay device for displaying a video picture; character generator meansfor generating signals representative of alphabetical, numerical and/orabstract characters; said picture display device receiving said signalsand displaying the alphabetical, numerical, and/or abstract charactersrepresented thereby; and control means for determining the value ofanalog data relating to the operation of said television set and forcausing said character generator means to generate signalsrepresentative of alphabetical, numerical and/or abstract characterswhich indicate said value of said analog data, said alphabetical,numerical and/or abstract characters consisting of a number ofcharacters proportional to the value of said analog data.
 4. Atelevision set, comprising:a picture display device for displaying avideo picture; character generator means for generating signalsrepresentative of alphabetical, numerical and/or abstract characters;said picture display device receiving said signals and displaying thealphabetical, numerical and/or abstract characters represented thereby;and control means for determining the value of analog data relating tothe operation of said television set and for causing said charactergenerator means to generate signals representative of alphabetical,numerical and/or abstract characters which indicate said value of saidanalog data, at least one of said alphabetical, numerical andl/orabstract characters indicating the type of data concerned.
 5. Atelevision set as claimed in claim 2, wherein said visual indication ofwhich of said data the user has last selected to adjust includes a givenadditional character alongside said data the user has selected toadjust.
 6. A television set as claimed in claim 2, wherein said visualindication of which of said data the user has last selected to adjustincludes a given color for the data the user has selected to adjust. 7.A television set as claimed in claim 1, wherein said control meansincludes a push-button panel for generating digital electronic signals,in response to actuation thereof by the user of said television set,which instructs said control means to change the value of said analogdata, said control means also causing said character generator means togenerate signals representative of alphabetical, numerical and/orabstract characters which indicate the value of said adjusted analogdata and also indicate that said analog data has been adjusted.
 8. Atelevision set as claimed in claim 7, wherein said control meansgenerates digital electronic signals indicative of said adjusted valueof said analog data, said control means further including a digital toanalog converter for converting said digital signal into an analogsignal, and a signal switch controlled by said control means forapplying said analog signal to that portion of said television circuitwhich will cause the value of said analog data to assume said adjustedvalue.
 9. A television set as claimed in any one of claims 1-6,additionally comprising a memory for memorizing values of said analogdata.
 10. A television set as claimed in claim 9, wherein the televisionset includes a tuning arrangement, capable of memory selection in whicheach of a series of keys is associated with a preselected and memorisedtelevision channel, and a memory circuit capable of memorising, for eachof the said channels, number signals representing the preselected valuesof the said analog data.
 11. A television set as claimed in any one ofclaims 1-6, additionally comprising means for producing an alarm whenthe said combination of alphabetical, numerical and/or abstractcharacters coincides with one or more preset combinations.